Mist oil lubricating compositions and methods

ABSTRACT

Lubrication compositions comprising from about 80% to about 99.9% of a synthetic ester lubricant; and from about 0.1% to about 8% of a polyalkyl methacrylate mist suppressant. The synthetic ester lubricant may be an adipate ester lubricant, which may be a ditridecyl adipate, a phthalate ester lubricants, such as diisononyl phthalates and ditridecyl phthalates, or mixtures thereof. The compositions may also comprise a highly branched isoparaffinic polyalphaolefin lubricant. The lubricating compositions may also comprise one or more additives.

INTRODUCTION

The present technology relates to lubricating compositions, particularlylubricating compositions suitable for use in mist oil lubricationsystems.

Lubricants are used to reduce friction between metal or other hardsurfaces that are in contact and in relative motion, so as to reducefriction. Without adequate lubrication, friction will result in heat andwear of the surfaces, ultimately destroying the surfaces in manysituations. In general, acceptable lubricants have physical propertiesthat allow them to be liquid and stable at the temperatures at which thelubricated surfaces operate, as well as acceptable viscosity, hydraulicstability, demulsibility (ability to release water), and oxidation andcorrosion resistance.

Many mechanical systems offer particular challenges in maintainingadequate lubrication of moving surfaces, due to such factors as theirmechanical configuration, forces applied to the moving surfaces, andenvironmental factors. The hydrocarbon processing industry, inparticular, presents significant lubricating issues relating to bearingsurfaces used in pumps and motors used in high pressure applications,often in corrosive environments. Similar challenges arise in thechemical processing industries, steel mills, pulp and paper mills,textile plants, and mining, for example.

Oil mist lubrication systems have been developed that are particularlyuseful in these industrial applications. In general, an oil mistlubrication system continuously atomizes oil into small particles andthen conveys and delivers the correct amount of lubricant to bearingsand metal surfaces for lubrication. In general, such systems can allowmoving surfaces to operate at significantly cooler temperatures, canoffer improved control of the amount of lubricant delivered, and canisolate reduce or eliminate sources of contamination from theenvironment.

Mist oil systems generally include an oil mist generator, one or morereclassifiers that deliver the oil to the bearing surfaces, and adistribution system to convey the mist oil from the generator to thereclassifier. In the generator, a high velocity air stream is passedthrough a vortex or venturi chamber which creates a vacuum or siphoningeffect that draws oil from a reservoir. The oil is atomized into smallparticles, such as in the 1 to 3 micron range, that are too small forlubrication but are easily transported by the air flow. The mist oilparticles are also too small to carry water or particulates throughoutthe piping system. This oil particle dispersion is thus referred to as a“dry mist.” At the reclassifier, the dry mist oil is passed through aturbulent area where the speed of the oil particles increases. Thisturbulence and increase in speed causes the particles to coalesce largeroil particles, forming a “wet mist” that can be deposited on thesurfaces to be lubricated.

One concern in mist lubrication systems is the creation of adequatelevels of wet mist, while controlling its application to the surfacesintended for lubrication. Control of the oil droplet particle size is animportant aspect of such systems. If particles are too large, the oilparticles may condense within the distribution system before reachingthe reclassifier(s). If too small, the particles may not coalesce,resulting in ineffective lubrication and “stray mist” that coalesces onunintended surfaces. In some situations stray mist can createenvironmental or safety issues.

Accordingly, mist oil lubrication compositions must meet stringentrequirements, both with respect to their properties as lubricants (asdiscussed above) and their ability to be effectively delivered in mistoil lubrication systems. There is a need, in particular, to develop suchlubricants that offer acceptable lubrication properties, while reducingor eliminating the generation of stray mist.

SUMMARY

The present technology provides lubrication compositions that arepreferably suitable for use in mist oil lubrication systems. Suchcompositions generally comprise

-   -   (a) from about 80% to about 99.9% of a synthetic ester        lubricant; and    -   (b) from about 0.1% to about 8% of a polyalkyl methacrylate mist        suppressant.        In various embodiments, the synthetic ester lubricant comprises        one or more adipate ester lubricants (such as a ditridecyl        adipate), one or more phthalate ester lubricants (such as        diisononyl phthalates and ditridecyl phthalates), and mixtures        thereof. The compositions may also comprise a highly branched        isoparaffinic polyalphaolefin lubricant. The lubricating        compositions may also comprise one or more additives selected        from the group consisting of rust inhibitors, yellow metal        deactivators, anti-wear agents, antioxidants, demulsifiers,        anti-foam agents, and extreme pressure agents.

DETAILED DESCRIPTION

The following description of technology is merely exemplary in nature ofthe subject matter, manufacture and use of one or more inventions, andis not intended to limit the scope, application, or uses of any specificinvention claimed in this application or in such other applications asmay be filed claiming priority to this application, or patents issuingtherefrom. A non-limiting discussion of terms and phrases intended toaid understanding of the present technology is provided at the end ofthis Detailed Description.

The present technology is directed to lubricant compositions containinga synthetic ester lubricant and a polyalkyl methacrylate mistsuppressant. The compositions are preferably suitable for use in mistoil lubricating systems, such as mist oil lubricating systems known inthe art.

Synthetic Ester Lubricant

The mist oil lubricant compositions of the present technology comprise asynthetic ester lubricant. Such ester lubricants are the reactionproducts of alcohols and acids. In various embodiments, the syntheticester lubricants are API (American Petroleum Institute) Group Vsynthetic fluids.

In various embodiments, synthetic ester lubricants comprise C₅ to C₁₈straight or branched chain alkyl esters of aromatic or aliphaticpolycarboxylic acids, having a viscosity of 10 to 700 cSt at 40° C. Forexample, esters may include esters of aromatic dicarboxylic acids having8 to 14 carbon atoms, aliphatic dicarboxylic acids having 4 to 12 carbonatoms, and cycloaliphatic dicarboxylic acids having 8 to 12 carbonatoms, or mixtures thereof. In some embodiments, the ester lubricantsare diesters formed by the reaction of monohydric alcohols, with dibasicacids. The diesters may be linear, branched or aromatic. For example,the alcohols may be branched C₉ to C₁₁ alcohols, branched C₁₁ to C₁₄alcohols, or mixtures thereof. Exemplary acids include adipic acid,azelaic acid, dodecanoic acid, fumaric acid, linoleic acid dimer,malonic acid, trimellitic and pyromellitic acid, maleic acid, subericacid, sebasic acid, phthalic acid, phthalic acid anhydride, alkylsuccinic acid, alkenyl succinic acid, and mixtures thereof. Exemplarymonohydric alcohols useful in such esters include those described above,such as isodecyl alcohol, n-octanol, 2-ethylhexanol, and isooctylalcohol, and mixtures thereof.

In various embodiments, the synthetic lubricant composition comprisesone or more adipate esters produced by the reaction of a monohydricalcohol with adipic acid. The adipate ester lubricant preferably has aviscosity of from about 5 to about 50, from about 10 to about 40, orfrom 20 to about 35 cSt, at 40° C. Adipate ester lubricants usefulherein are commercially available, including Esterex A51, sold byExxonMobil Chemical Company, Houston, Tex., USA, having a viscosity ofabout 27 cSt at 40° C. In general, viscosities of compositions andcomponents of the present technology may be measured by techniques knownin the art, such as described in ASTM D445, “Standard Test for KinematicViscosity of Transparent and Opaque Liquids (and Calculation of DynamicViscosity,” ASTM International, West Coshohocken, Pa., U.S.A.

In various embodiments, the synthetic lubricant composition comprisesone or more phthalate ester lubricants produced by the reaction ofmonohydric alcohols with phthalic anhydride. The phthalate esterlubricant preferably has a viscosity of from about 20 to about 150, fromabout 30 to about 100, or from about 35 to about 90 cSt, at 40° C. Thephthalate ester lubricant may comprise a mixture of lubricants, such asa mixture of a first phthalate ester lubricant having a viscosity offrom about 20 to about 70, from about 30 to about 50, or from about 35to about 40 cSt, at 40° C., with a second phthalate ester lubricanthaving a viscosity of from about 50 to about 110, from about 70 to about100, or from about 80 to about 90 cSt, at 40° C. Phthalate esterlubricants useful herein are commercially available, including Esterex™P61 ditridecyl phthalate synthetic fluid, sold by ExxonMobil ChemicalCompany, Houston, Tex., USA, having a viscosity of about 38 cSt at 40°C., and Esterex™ P81 tridecyl phthalate synthetic fluid, sold byExxonMobil Chemical Company, Houston, Tex., USA, having a viscosity ofabout 84 cSt at 40° C.

In various embodiments, the synthetic lubricant comprises a mixture ofesters, such as an adipate ester with one or more additional esterlubricants. For example, the synthetic ester lubricant may comprise amixture of branched chain tridecyl phthalate and tridecyl adipatewherein the mixture is such that from about 80% to about 85% by weightof the mist lubricant is ditridecyl phthalate and from about 10% toabout 15% is ditridecyl adipate.

Optional Lubricants

In various embodiments, the mist oil compositions of the presenttechnology comprise one or more optional lubricants, in addition to asynthetic ester lubricant. Such lubricants may be API Group III, GroupIV, or Group V non-ester lubricants. For example, the compositions maycontain a hydrogenated polyalphaolefin (PAO) synthetic lubricant, madeby polymerizing an alpha-olefin. In some embodiments, the PAO syntheticlubricant has a viscosity of from about 20 to about 70, from about 30 toabout 60, or from about 40 to about 55 cSt, at 40° C. PAO syntheticlubricants useful herein are commercially available, includingSpectrasyn 8, sold by ExxonMobil Chemical Company, Houston, Tex., USA,having a viscosity of about 48 cSt at 40° C.

Polyalkyl Methacrylate Mist Suppressant

The mist oil compositions of the present technology comprise one or moremist suppressants that improve the stray mist characteristics of thecompositions, when used in mist lubricant systems (such as conventionalmist lubricant systems known in the art) relative to compositions nothaving the mist suppressants. Without limiting the mechanism, functionor utility of present technology, in various embodiments the mistsuppressant allows formulation of mist oil lubricant compositions havingreduced amounts of sub-micron oil particles when atomized, such as fromabout 0.2 to about 7 microns in size. In various embodiments, theparticle size is from about 0.4 to about 6 microns, from about 0.5 toabout 5 microns, or from about 1 to about 5 microns. For example, theparticle size may be from about 3 to about 5 microns in someembodiments. In other embodiments, the particle size may be from about0.4 to about 0.8 microns. In various embodiments, the mist oilsuppressant affords reduced stray mist, while maintaining or improvinglubricant properties (e.g., increased levels of reclassified oil) of themist lubricant. The mist properties of the compositions of the presenttechnology may be measured by techniques known in the art, such asdescribed in ASTM D3705, “Standard Test Method for Misting Properties ofLubricating Fluids,” ASTM International, West Coshohocken, Pa., U.S.A.

The mist suppressant is preferably a methacrylate, preferably apolyalkyl methacrylate (PAMA). Methacrylates among those useful hereininclude n-dodecyl methacrylate (DDMA), n-octadecyl methacrylate (ODMA)and dimethylaminoethyl methacrylate (DMAEMA), and mixtures thereof. Forexample, the methacrylate mist suppressant may be a C₆ to C₁₈methacrylate. In various embodiments, the mist suppressant has aviscosity of from about 80 to about 2500 cSt at 40° C., or from about200 to about 2200 cSt at 40° C., or from about 1000 to about 2000 cSt at40° C. Methacrylate synthetic lubricants useful herein are commerciallyavailable, including Viscoplex 8450, sold by Evonik Industries, Essen,Germany; HiTech® polymethacrylates, sold by Afton Chemical Corporation,Richmond, Va., U.S.A.; and polymethacrylate rheology additives sold byThe Lubrizol Corporation, Wickliffe, Ohio, U.S.A.

Optional Additives

Mist oil compositions of the present technology optionally comprise oneor more additive materials. In various embodiments, additive materialsuseful herein include rust inhibitors, yellow metal deactivators,anti-wear agents, antioxidants, demulsifiers, anti-foam agents, andextreme pressure agents, and mixtures thereof. Such additives includethose known in the art.

For example, anti-wear agents and extreme pressure agents includesulfurized fatty acid or fatty acid esters, organopolysulfides,organophosphorous derivatives such as amine phosphates anddialkylphosphates. In some embodiments, compositions comprise triphenylphosphorothionate.

Rust and corrosion inhibitors include dibasic acids, quinolines andquinones, ester and amide derivatives of alkenyl succinic anhydrides,and metal alkyl sulfonates, and mixtures thereof. In some embodiments,compositions comprise benzotriazole and alkylated benzotriazole andalkylated amino methylene benzotriazoles, wherein the alkyl has from 1to 20 carbons.

Demulsifiers include alkoxyalkylated alkyl phenols, monohydric alcohols,alkylene glycols, and combinations thereof. In some embodiments,compositions comprise an oxyalkylated (e.g., 70% propylene oxide, 30%ethylene oxide) amylphenol resin.

Anti-foam agents include silicone oils, acrylates and the like. In someembodiments, compositions comprise polydimethyl siloxane.

For example, in some embodiments, compositions comprise polyether glycolas a demulsifier, butylated triphenyl phosphorothionate as ananti-wear/extreme pressure agent, amine phosphates as an anti-wearagent, a tolutriazole derivative as a yellow metal deactivator, atolutriazole compound as an antioxidant, a substituted di-phenyl amineas an antioxidant, a dodecenylsuccinic acid reaction product as a rustinhibitor, and polydimethyl siloxane as an anti-foam agent.

Additives are optionally present in the mist oil compositions at totallevels of from about 0.005% to about 10%, from about 0.01% to about 8%,or from about 1% to about 5% of the composition. In some embodiments,each material that comprises an additive will be present at a level offrom about 0.005% to about 3%, or from about 0.01% to about 2%.

Formulations

The compositions of the present technology may be formulated asappropriate to the desired end-use method. It is understood that thespecific formulation may vary depending on the environment and operatingcharacteristics of the mist oil lubrication system in which thecompositions are to be used, as well as the surfaces and associatedequipment to be lubricated.

The mist oil lubricants may be formulated so as to have a desiredviscosity, for example, to improve performance at the operatingtemperature of the lubrication system in which the lubricant is to beused. In general, the mist oil lubricants of the present technology havea viscosity of from about 10 to about 700 cSt at 40° C. In variousembodiments, the viscosity may be of from about 20 to about 500 cSt at40° C., from about 20 to about 200 cSt at 40° C., or from about 30 toabout 160 cSt at 40° C. For example, mist oil lubricants may haveviscosities of from about 30 to about 35 (e.g., about 32) cSt at 40° C.,from about 40 to about 50 (e.g., about 46) cSt at 40° C., from about 65to about 70 (e.g., about 68) cSt at 40° C., from about 95 to about 105(e.g., about 100) cSt at 40° C., or from about 145 to about 155 (e.g.,about 150) cSt at 40° C. The desired lubricant viscosity may be obtainedby selection of components having desired viscosities, such as bycombination of synthetic ester lubricants, optional lubricants, mistsuppressants, and optional materials, including such componentsdescribed above.

In general, ranges of each component may be included at the levelsexemplified above. In various embodiments, compositions comprise:

-   -   (a) from about 0% to about 96.5% of an adipate ester lubricant        having a viscosity of from about 20 to about 35 cSt at 40° C.;    -   (b) from about 0% to about 96.5% of a phthalate ester lubricant        having a viscosity of from about 35 to about 90 cSt at 40° C.;    -   (c) from about 1% to about 10% of a highly branched        isoparaffinic polyalphaolefin lubricant having a viscosity of        from about 40 to about 55 cSt at 40° C.;    -   (d) from about 0.1% to about 8% of a polyalkyl methacrylate mist        suppressant; and    -   (e) from about 0.01% to about 5% of an additive selected from        the group consisting of rust inhibitors, yellow metal        deactivators, anti-wear agents, antioxidants, demulsifiers,        anti-foam agents, extreme pressure agents, and mixtures thereof;    -   wherein the total level of the adipate ester lubricant and the        phthalate ester lubricant is from about 80% to about 96.5%,        preferably from about 90% to about 96%.        In some embodiments, the phthalate ester lubricant is selected        from the group consisting of diisononyl phthalates, ditridecyl        phthalates, and mixtures thereof. For example, such a        composition may comprise from about 0.5% to about 75% of a        diisononyl phthalate lubricant and from about 0.5% to about 92%        of a ditridecyl phthalate lubricant. In some embodiments, each        material that comprises the additive will be present at a level        of from about 0.01% to about 3%, or from about 0.5% to about 2%.

Methods

The present technology also provides methods of lubricating a surface,comprising applying a mist lubricant to the surface, the mist lubricantcomprising

-   -   (a) from about 80% to about 99.1% of a synthetic ester        lubricant; and    -   (b) from about 0.1% to about 8% of a polyalkyl methacrylate mist        suppressant.        The mist lubricant can be a composition of the present        technology, as described above. The surface may comprise any        solid material, such as a first surface in contact with a second        surface. The second and first surfaces may comprise the same or        different materials. In various embodiments, the surface is a        metal, such as steel, brass, copper, tin, or lead.

Methods of the present invention may employ any mist oil lubricatingsystem, including such systems as are known in the art. For example, insuch systems a mist of lubricant is generated in air under pressure andpneumatically transported to a metal surface to be lubricated, coalescedinto larger droplets and deposited on a metal surface, using the mistlubricant of the present technology as the lubricant. Such systems maybe used with a variety of equipment, including shafts, bearings, sealsand other components of equipment used in hydrocarbon processing (suchas oil exploration, production, and refining), chemical processing,steel mills, pulp and paper mills, textile plants, and mining.

EXAMPLES

The present technology is further illustrated through the followingnon-limiting examples. In particular mist oil lubricant compositions ofthe present technology may be formulated as follows.

Example, % (by weight) Component 1 2 3 4 5 phthalate ester lubricant,viscosity — 33.5 74.7 34.6 — 38 cSt at 40° C. phthalate ester lubricant,viscosity — — 17.8 57.2 91.5 84 cSt at 40° C. adipate ester lubricant,viscosity 96 60 — — — 27 cSt at 40° C. polyalphaolefin (PAO) synthetic —— 1 1 — lubricant polymethacrylate mist 1 3.5 3.5 4.2 5.5 suppressanttolutriazole antioxidant 1 1 1 1 1 polyether glycol demulsifier 0.1 0.10.1 0.1 0.1 triphenyl phosphorothionate/ 0.6 0.6 0.6 0.6 0.6 C11-C14alkyl amine phosphate antiwear and extreme pressure agentdodecenylsucccinic acid reaction 0.2 0.2 0.2 0.2 0.2 productanti-rust/corrosion inhibitor substituted diphenyl amine 1 1 1 1 1antioxidant dimethyl siloxane antifoam agent 0.1 0.1 0.1 0.1 0.1viscosity 32 46 68 100 150

Summary of Exemplary Embodiments

Without limit the scope, application, or uses of the present technologyas described above, or of any specific invention claimed in thisapplication or in such other applications as may be filed claimingpriority to this application, or patents issuing therefrom, thefollowing sub-paragraphs provide a non-limiting listing of embodimentsand combined embodiments within the scope of the present technology.

-   -   A1. A mist oil lubricating composition comprising:    -   (a) from about 80% to about 99.9% of a synthetic ester        lubricant; and    -   (b) from about 0.1% to about 8% of a polyalkyl methacrylate mist        suppressant.    -   A2. The mist oil lubricating composition according to        Sub-Paragraph A1, wherein the lubricant has a viscosity of from        about 10 to about 700 cSt at 40° C., preferably from about 20 to        about 200 cSt at 40° C.    -   A3. The mist oil lubricating composition according to        Sub-Paragraph A1 or Sub-Paragraph A2, wherein the lubricant        comprises an adipate ester lubricant, a phthalate ester        lubricant, or mixtures thereof.    -   A4. The mist oil lubricating composition according to        Sub-Paragraph A3, wherein the adipate ester lubricant is a        ditridecyl adipate.    -   A5. The mist oil lubricating composition according to        Sub-Paragraph A3 or Sub-Paragraph A4, wherein the adipate ester        lubricant is present at a level of about 50% to about 99% of the        composition.    -   A6. The mist oil lubricating composition according to any of        Sub-Paragraphs A3 trough A5, wherein the adipate ester lubricant        has a viscosity of from about 20 to about 35 cSt at 40° C.    -   A7. The mist oil lubricating composition according to        Sub-Paragraphs A4-A6, wherein the lubricant further comprises a        phthalate ester lubricant.    -   A8. The mist oil lubricating composition according any of the        proceeding claims, wherein the phthalate ester lubricant is        selected from the group consisting of diisononyl phthalates,        ditridecyl phthalates, and mixtures thereof.    -   A9. The mist oil lubricating composition according to        Sub-Paragraph A8, wherein the phthalate ester lubricant is        present at a level of about 50% to about 99.9%, preferably from        about 90% to about 96.5% of the composition.    -   A10. The mist oil lubricating composition according to any of        the preceding claims, wherein the mist suppressant has a        viscosity of from about 80 to about 2,500 cSt at 100° C.    -   A11. The mist oil lubricating composition according to        Sub-Paragraph A10, wherein the mist suppressant is a C₆ to C₁₈        methacrylate.    -   A12. The mist oil lubricating composition according to any of        the preceding claims, further comprising from about 0.1% to        about 10% of a highly branched isoparaffinic polyalphaolefin        lubricant.    -   A13. The mist oil lubricating composition according to        Sub-Paragraph A12, wherein the polyalphaolefin lubricant has a        viscosity of from about 40 to about 55 cSt at 40° C.    -   A14. The mist oil lubricating composition according to any of        the preceding claims, further comprising an additive selected        from the group consisting of rust inhibitors, yellow metal        deactivators, anti-wear agents, antioxidants, demulsifiers,        anti-foam agents, extreme pressure agents, and mixtures thereof.    -   A14. The mist oil lubricating composition according to        Sub-Paragraph A13, wherein the additive is present at a level of        from about 0.01% to about 5% of the composition.    -   A15. The mist oil composition according to any of the preceding        claims having a viscosity grade of 30 to about 160 cSt at 40°        C., such as a viscosity of from about 30 to about 35 cSt at 40°        C., from about 40 to about 50 cSt at 40° C., from about 65 to        about 70 cSt at 40° C., from about 95 to about 105 cSt at 40°        C., or from about 145 to about 155 cSt at 40° C.    -   B1. A mist oil lubricating composition comprising:    -   (a) from about 0% to about 96.5% of an adipate ester lubricant        having a viscosity of from about 20 to about 35 cSt at 40° C.;    -   (b) from about 0% to about 96.5 of a phthalate ester lubricant        having a viscosity of from about 35 to about 90 cSt at 40° C.;    -   (c) from about 1% to about 10% of a highly branched        isoparaffinic polyalphaolefin lubricant having a viscosity of        from about 40 to about 55 cSt at 40° C.;    -   (d) from about 0.1% to about 8% of a polyalkyl methacrylate mist        suppressant; and    -   (e) from about 0.01% to about 5% of an additive selected from        the group consisting of rust inhibitors, yellow metal        deactivators, anti-wear agents, antioxidants, demulsifiers,        anti-foam agents, extreme pressure agents, and mixtures thereof;    -   wherein the total level of the adipate ester lubricant and the        phthalate ester lubricant is from about 80% to about 96.5%,        preferably from about 90% to about 96%, and the composition has        a viscosity of from about 20 to about 200 cSt at 40° C.    -   B2. The mist oil lubricating composition according to        Sub-Paragraph C1, wherein the phthalate ester lubricant is        selected from the group consisting of diisononyl phthalates,        ditridecyl phthalates, and mixtures thereof.    -   B3. The mist oil lubricating composition according to        Sub-Paragraph C2, comprising from about 0.5% to about 75% of a        diisononyl phthalate lubricant and from about 0.5% to about 92%        of a ditridecyl phthalate lubricant.    -   C1. A method of mist oil lubrication of a surface, comprising        applying a mist lubricant to the surface, the mist lubricant        comprising:    -   (a) from about 90% to about 99.9% of a synthetic ester        lubricant; and    -   (b) from about 0.1% to about 8% of a polyalkyl methacrylate mist        suppressant.    -   C2. The method of Sub-paragraph B1, wherein the mist lubricant        is a composition according to any of Sub-Paragraphs A2-A15 or        B1-B3.

NON-LIMITING DISCUSSION OF TERMINOLOGY

The headings (such as “Introduction” and “Summary”) and sub-headingsused herein are intended only for general organization of topics withinthe present disclosure, and are not intended to limit the disclosure ofthe technology or any aspect thereof. In particular, subject matterdisclosed in the “Introduction” may include novel technology and may notconstitute a recitation of prior art. Subject matter disclosed in the“Summary” is not an exhaustive or complete disclosure of the entirescope of the technology or any embodiments thereof. Classification ordiscussion of a material within a section of this specification ashaving a particular utility is made for convenience, and no inferenceshould be drawn that the material must necessarily or solely function inaccordance with its classification herein when it is used in any givencomposition and method.

The description and specific examples, while indicating embodiments ofthe technology, are intended for purposes of illustration only and arenot intended to limit the scope of the technology. Moreover, recitationof multiple embodiments having stated features is not intended toexclude other embodiments having additional features, or otherembodiments incorporating different combinations of the stated features.Specific examples are provided for illustrative purposes of how to makeand use the compositions and methods of this technology and, unlessexplicitly stated otherwise, are not intended to be a representationthat given embodiments of this technology have, or have not, been madeor tested. Equivalent changes, modifications and variations of someembodiments, materials, compositions and methods can be made within thescope of the present technology, with substantially similar results.

As used herein, the words “desire” or “desirable” refer to embodimentsof the technology that afford certain benefits, under certaincircumstances. However, other embodiments may also be desirable, underthe same or other circumstances. Furthermore, the recitation of one ormore desired embodiments does not imply that other embodiments are notuseful, and is not intended to exclude other embodiments from the scopeof the technology.

As used herein, the words “preferred” and “preferably” refer toembodiments of the technology that afford certain benefits, undercertain circumstances. However, other embodiments may also be preferred,under the same or other circumstances. Furthermore, the recitation ofone or more preferred embodiments does not imply that other embodimentsare not useful, and is not intended to exclude other embodiments fromthe scope of the technology.

As used herein, the word “include,” and its variants, is intended to benon-limiting, such that recitation of items in a list is not to theexclusion of other like items that may also be useful in the materials,compositions, devices, and methods of this technology. Similarly, theterms “can” and “may” and their variants are intended to benon-limiting, such that recitation that an embodiment can or maycomprise certain elements or features does not exclude other embodimentsof the present technology that do not contain those elements orfeatures.

Although the open-ended term “comprising,” as a synonym ofnon-restrictive terms such as including, containing, or having, is usedherein to describe and claim embodiments of the present technology,embodiments may alternatively be described using more limiting termssuch as “consisting of” or “consisting essentially of.” Thus, for anygiven embodiment reciting materials, components or process steps, thepresent technology also specifically includes embodiments consisting of,or consisting essentially of, such materials, components or processesexcluding additional materials, components or processes (for consistingof) and excluding additional materials, components or processesaffecting the significant properties of the embodiment (for consistingessentially of), even though such additional materials, components orprocesses are not explicitly recited in this application. For example,recitation of a composition or process reciting elements A, B and Cspecifically envisions embodiments consisting of, and consistingessentially of, A, B and C, excluding an element D that may be recitedin the art, even though element D is not explicitly described as beingexcluded herein.

As referred to herein, all compositional percentages are by weight ofthe total composition, unless otherwise specified. Disclosures of rangesare, unless specified otherwise, inclusive of endpoints and includedisclosure of all distinct values and further divided ranges within theentire range. Thus, for example, a range of “from A to B” or “from aboutA to about B” is inclusive of A and of B. Disclosure of values andranges of values for specific parameters (such as temperatures,molecular weights, weight percentages, etc.) are not exclusive of othervalues and ranges of values useful herein. It is envisioned that two ormore specific exemplified values for a given parameter may defineendpoints for a range of values that may be claimed for the parameter.For example, if Parameter X is exemplified herein to have value A andalso exemplified to have value Z, it is envisioned that Parameter X mayhave a range of values from about A to about Z. Similarly, it isenvisioned that disclosure of two or more ranges of values for aparameter (whether such ranges are nested, overlapping or distinct)subsume all possible combination of ranges for the value that might beclaimed using endpoints of the disclosed ranges. For example, ifParameter X is exemplified herein to have values in the range of 1-10,or 2-9, or 3-8, it is also envisioned that Parameter X may have otherranges of values including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3, 3-10, and3-9.

What is claimed is:
 1. A mist oil lubricating composition comprising:(a) from about 80% to about 99.9% of a synthetic ester lubricant; and(b) from about 0.1% to about 8% of a polyalkyl methacrylate mistsuppressant.
 2. The mist oil lubricating composition according to claim1, wherein the lubricant has a viscosity of from about 10 to about 700cSt at 40° C.
 3. The mist oil lubricating composition according to claim1, wherein the lubricant comprises an adipate ester lubricant, aphthalate ester lubricant, or mixtures thereof.
 4. The mist oillubricating composition according to claim 3, wherein the adipate esterlubricant is a ditridecyl adipate.
 5. The mist oil lubricatingcomposition according to claim 1, wherein the ester lubricant is presentat a level of about 90% to about 96% of the composition.
 6. The mist oillubricating composition according to claim 1, wherein the adipate esterlubricant has a viscosity of from about 20 to about 35 cSt at 40° C. 7.The mist oil lubricating composition according to claim 1, wherein thephthalate ester lubricant is selected from the group consisting ofdiisononyl phthalates, ditridecyl phthalates, and mixtures thereof. 8.The mist oil lubricating composition according to claim 1, wherein thephthalate ester lubricant is present at a level of about 50% to about99.9% of the composition.
 9. The mist oil lubricating compositionaccording to claim 1, wherein the mist suppressant has a viscosity offrom about 80 to about 2,500 cSt at 100° C.
 10. The mist oil lubricatingcomposition according to claim 9, wherein the mist suppressant is a C₆to C₁₈ methacrylate.
 11. The mist oil lubricating composition accordingclaim 1, further comprising from about 0.1% to about 10% of a highlybranched isoparaffinic polyalphaolefin lubricant.
 12. The mist oillubricating composition according to claim 11, wherein thepolyalphaolefin lubricant has a viscosity of from about 40 to about 55cSt at 40° C.
 13. The mist oil lubricating composition according toclaim 1, further comprising an additive selected from the groupconsisting of rust inhibitors, yellow metal deactivators, anti-wearagents, antioxidants, demulsifiers, anti-foam agents, extreme pressureagents, and mixtures thereof.
 14. The mist oil lubricating compositionaccording to claim 13, wherein the additive is present at a level offrom about 0.01% to about 5% of the composition.
 15. The mist oilcomposition according to claim 1, having a viscosity of 30 to about 160cSt at 40° C.
 16. A method of mist oil lubrication of a surface,comprising applying a mist lubricant to the surface, the mist lubricantcomprising: (a) from about 90% to about 99.9% of a synthetic esterlubricant; and (b) from about 0.1% to about 8% of a polyalkylmethacrylate mist suppressant.
 17. A mist oil lubricating compositioncomprising: (a) from about 0% to about 96.5% of an adipate esterlubricant having a viscosity of from about 20 to about 35 cSt at 40° C.;(b) from about 0% to about 96.5 of a phthalate ester lubricant having aviscosity of from about 35 to about 90 cSt at 40° C.; (c) from about 1%to about 10% of a highly branched isoparaffinic polyalphaolefinlubricant having a viscosity of from about 40 to about 55 cSt at 40° C.;(d) from about 0.1% to about 8% of a polyalkyl methacrylate mistsuppressant; and (e) from about 0.01% to about 5% of an additiveselected from the group consisting of rust inhibitors, yellow metaldeactivators, anti-wear agents, antioxidants, demulsifiers, anti-foamagents, extreme pressure agents, and mixtures thereof; wherein the totallevel of the adipate ester lubricant and the phthalate ester lubricantis from about 80% to about 96.5%, preferably from about 90% to about96%, and the composition has a viscosity of from about 20 to about 200cSt at 40° C.
 18. The mist oil lubricating composition according toclaim 17, wherein the phthalate ester lubricant is selected from thegroup consisting of diisononyl phthalates, ditridecyl phthalates, andmixtures thereof.
 19. The mist oil lubricating composition according toclaim 18, comprising from about 0.5% to about 75% of a diisononylphthalate lubricant and from about 0.5% to about 92% of a ditridecylphthalate lubricant.